Congrats on the great work. Defensive football I feel is the most satisfying way to play FM, there is no other feeling than frustrating your opponent and then nicking a goal in the dying seconds.
My question for you is simple and hopefully something I haven't missed. You stated you chose the narrow 4-1-2-1-2 for a challenge as it would cause issues down your wings. So bearing in mind you've passed that challenge with flying colours, if you could choose ANY formation for a defensive set up, which would it be and how would you look to implement it? (Roles, Strategy etc).